1. Field of the Invention
The present invention relates to food supplements for animals and, in particular, a dry sweetener supplement for animal feed.
2. Description of the Prior Art.
The addition of sweeteners to animal feeds is an old and well-known method of inducing animals to intake more food, or to intake food that is not especially palatable. It is desirable that such sweeteners be low-cost so that the cost of the animal feed is not substantially increased, if at all.
One such sweetener that has been used extensively in the past is molasses. Molasses has been used in attempts to make palatable animal feeds from agricultural by-products which are generally considered not palatable. For example, molasses has been used to coat seed hulls such as sunflowers. A process to impregnate oat hulls with molasses is described in U.S. Pat. No. 3,395,019. The Fiala U.S. Pat. No. 4,012,535 describes a process for impregnating bagasse pith with molasses.
Attempts have also been made to use whey, a cheese by-product of considerable proportion, as an animal feed or animal feed supplement. Whey in the past has been dumped onto fields, in ditches or into rivers and streams. Various governmental regulatory agencies have, for the most part, stopped such practice. Whey is now used extensively as a food additive. Whey's two largest constituents, proteins and lactose, are removed from the whey for use as food additives. The Thomas U.S. Pat. No. 4,001,198 describes a method of recovering nutrients from cheese whey by sequential ultrafiltration, each ultrafiltration step removing as permeate substantial amounts of water and dissolved solids from the respective concentrates. Initially, protein is removed from the whey, then the lactose is removed from the permeate.
A number of patents describe various animal feed or animal feed supplements using whey treated in various manners. For example, the Miller U.S. Pat. No. 4,542,032 is directed to a feed supplement that treats whey with a bisulfite moiety to react the lactose present in the whey and form a lactose-bisulfite addition product. The lactose-bisulfite addition product is more soluble in water than lactose, therefore, the treated whey may be condensed more by removing water without sedimentation of the lactose during condensation or storage. The whey is condensed to about 40-50% solids content. The whey may be utilized directly as an animal feed, or can be blended with another source of nutrients to provide a full ration animal feed.
The Schanze U.S. Pat. No. 4,357,358 describes an animal feedstuff that includes from about 25% to 95% solid structured fibrous agricultural by-product, such as cereal, and from about 75% to about 5% of at least one digestible industrial by-product with nutrient value, one of which could be whey. The whey is a low lactose, protein-enriched whey.
The du Chaffaut et al. U.S. Pat. No. 4,165,389 describes a fermentation process for the production of protein-rich animal feedstuff from a liquid dairy by-product containing lactose and lactic acid which includes cultivating a lactose and lactic acid utilizing strain of a yeast of the genus U.C. Kluyveromyses in the presence of a gas-containing free oxygen and a broth comprising a nitrogen source, the liquid dairy by-product and added nicotinic acid.
The Haugh U.S. Pat. No. 2,508,112 describes a method of making an animal feed mixture including 15%-70% lactose and remainder including protein feed materials. The moisture of the mixture is adjusted to a point where the mixture contains from about 10%-30% water thereby producing a plastic mass, extruding the mixture under heavy pressure, and subdividing the extruded material into pellets.
The Peterson U.S. Pat. No. 4,202,909 describes a method of treating whey to obtain a high yield of relatively pure lactose and salt products. The products are produced from a permeate resulting from ultrafiltration of whey by precipitating calcium and citrate salts from the permeate without substantial precipitation of phosphate salts. The precipitation is done by concentrating the permeate to a solids content of about 40-45% and holding at about 180.degree. F. to 200.degree. F. for 30-90 minutes. The precipitated solids are removed from the permeate and further concentrated and the lactose is removed by crystallization. The permeate is then further spray-dried to produce a product that contains the remaining lactose and is useful as a food or feed.
The Chambers et al. U.S. Pat. No. 4,547,386 describes a process for forming an animal feed block from whey. By-product whey is concentrated to form a whey concentrate having a solids content of at least about 45%. Calcium phosphate is added to the concentrate and the concentrate is then adjusted to a ph of between 4.0 and about 6.0. The concentrate is then poured into a mold and dried to form the feed block.
The Austin et al Patent describes an animal feed that is fortified with a lactose-rich whey product. By lactose-rich is meant that the whey has a lactose content greater than 20% of the solid material, such as dried whole whey, condensed whey and whey solids. The animals are fed a lactose content that is above the normal digested limit of lactose for the animal, providing that the feed is concomitantly supplemented with 0.5% to 5% of a water insoluble polymer based predominantly on N-acetyl-D-glucosamine glycoside.
Others have attempted to mix both molasses and whey to produce an animal feed supplement. In the Schroeder et al. U.S. Pat. No. 4,160,041, a method is described wherein a hydratable metal oxide, such as calcium oxide, is added to a concentrated dispersion of a water soluble sugar, such as molasses, whey and the like to hydrate the metal oxide. After sufficient hydration has occurred, a water soluble phosphate such as phosphoric acid, is added to solidify the product.
The Bode U.S. Pat. No. 3,505,073 describes a process that transforms a dry-feed carbohydrate material, such as whey or molasses, to lactic acid. The dry lactated product is then suitable for use in a feed formulation for animals.